1,319 research outputs found

    Annual Compendium of Disability Statistics: 2015

    Get PDF
    Statistics are a powerful tool—in research, policymaking, program evaluation, and advocacy. They are used to frame the issues, monitor current circumstances and progress, judge the effectiveness of policies and programs, make projections about the future, and predict the costs of potential policy changes. In the United States, statistics about the population with disabilities and about the government programs that serve people with disabilities—disability statistics—are often difficult to find. Numerous government agencies generate and publish disability statistics, and as a result, disability statistics are scattered and buried in documents and websites all across the federal government. The Annual Disability Statistics Compendium is a publication of statistics about people with disabilities and about the government programs which serve them. It is modeled after the Statistical Abstracts of the United States, published yearly by the U.S. Department of Commerce. The Compendium is designed to serve as a summary of government statistics

    Action of lithium in radiation hardened silicon solar cells Quarterly report, 23 Apr. - 15 Jul. 1968

    Get PDF
    Recovery properties of lithium containing p-n silicon solar cells after radiation damag

    Study to determine and improve design for lithium-doped solar cells Quarterly report, 1 Apr. - 30 Jun. 1970

    Get PDF
    Lithium action effects on spontaneous annealing of radiation damage in bulk silicon and silicon solar cell

    Radiation damage in lithium-containing solar cells Final report, 21 Jun. 1966 - 20 Mar. 1968

    Get PDF
    Interaction of lithium with defects induced in silicon solar cells by one MeV electron bombardmen

    Prediction and measurement of radiation damage to CMOS devices on board spacecraft

    Get PDF
    The CMOS Radiation Effects Measurement (CREM) experiment is presently being flown on the Explorer-55. The purpose of the experiment is to evaluate device performance in the actual space radiation environment and to correlate the respective measurements to on-the-ground laboratory irradiation results. The experiment contains an assembly of C-MOS and P-MOS devices shielded in front by flat slabs of aluminum and by a practically infinite shield in the back. Predictions of radiation damage to C-MOS devices are based on standard environment models and computational techniques. A comparison of the shifts in CMOS threshold potentials, that is, those measured in space to those obtained from the on-the-ground simulation experiment with Co-60, indicates that the measured space damage is smaller than predicted by about a factor of 2-3 for thin shields, but agrees well with predictions for thicker shields

    Miniature High-Let Radiation Spectrometer for Space and Avionics Applications

    Get PDF
    This paper reports on the design and characterization of a small, low power, and low weight instrument, a High-LET Radiation Spectrometer (HiLRS), that measures energy deposited by heavy ions in microelectronic devices. The HILRS operates on pulse-height analysis principles and is designed for space and avionics applications. The detector component in the instrument is based on large scale arrays of p-n junctions. In this system, the pulse amplitude from a particle hit is directly proportional to the particle LET. A prototype flight unit has been fabricated and calibrated using several heavy ions with varying LETs and protons with several energies. The unit has been delivered to the Ballistic Missile Defense Organization (BMDO) c/o the Air Force Research Laboratory in Albuquerque, NM, for integration into the military Space Technology Research Vehicle (STRV), a US-UK cooperative mission. Another version of HILRS is being prepared for delivery in April to the Hubble Space Telescope (HST) project, to fly on the HST Orbital Systems Test (HOST) Platform on a shuttle mission

    CRRES microelectronics package flight data analysis

    Get PDF
    A detailed in-depth analysis was performed on the data from some of the CRRES MEP (Microelectronics Package) devices. These space flight measurements covered a period of about fourteen months of mission lifetime. Several types of invalid data were identified and corrections were made. Other problems were noted and adjustments applied, as necessary. Particularly important and surprising were observations of abnormal device behavior in many parts that could neither be explained nor correlated to causative events. Also, contrary to prevailing theory, proton effects appeared to be far more significant and numerous than cosmic ray effects. Another unexpected result was the realization that only nine out of thirty-two p-MOS dosimeters on the MEP indicated a valid operation. Comments, conclusions, and recommendations are given

    The challenge of extra-intra craniometry: a computer-assisted three-dimensional approach on the equine skull

    Get PDF
    Background: The topographical correlations between certain extracranial and intracranial osseous points of interest (POIs), and their age-related changes, are indispensable to know for a diagnostical or surgical access to intracranial structures; however, they are difficult to assess with conventional devices. Materials and methods: In this pilot study, the 3-dimensional coordinates of extra-/intracranial POIs were determined, thus avoiding perspective distortions that used to be intrinsic problems in 2-dimensional morphometry. The data sets were then analysed by creating virtual triangles. The sizes, shapes, and positions of these triangles described the extent and the directions of the age-related shifts of the POIs. A selection of extracranial and intracranial POIs were marked on half skulls of four warmblood horses in two age groups (young: 6 weeks, n = 2; old: 14 and 17 years, n = 2). The x-, y-, and z-coordinates of these POIs were determined with a measurement arm (FaroArm Fusion, FARO Europe®). Direct distances between the POIs as well as their indirect distances on the x-, y-, and z-axis, and angles were calculated. Results: The analysed virtual triangles revealed that some parts of the skull grew in size, but did not change in shape/relative proportions (proportional type of growth, as displayed by POI A and POI B at the Arcus zygomaticus). The same POIs (A and B) remained in a very stable relationship to their closest intracranial POI at the Basis cranii on the longitudinal axis, however, shifted markedly in the dorso-lateral direction. In contrast, a disproportional growth of other parts of the cranium was, for example, related to POI C at the Crista nuchae, which shifted strongly in the caudal direction with age. A topographically stable reference point (so-called anchor point) at the Basis cranii was difficult to determine. Conclusions: Two candidates (one at the Synchondrosis intersphenoidalis, another one at the Synchondrosis sphenooccipitalis) were relatively stable in their positions. However, the epicentre of (neuro-)cranial growth could only be pinpointed to an area between them
    • …
    corecore